Deployable structure

Abstract

A deployable structure comprising a side wall having a plurality of segments which make the side wall a tube-like shape as a whole. Four adjacent segments are connected with one another at one point to make one module. The folding patterns of the segments along the connecting creases have two purposes, one of which is a closing pattern to reduce an inner angle between connected segments adjacent in a circumferential direction of the side wall, accompanied with a folding in a direction of a central axis, the other of which is an opening pattern to enlarge the inner angle between connected segments adjacent in the circumferential direction of the side wall, accompanied with a folding in the direction of the central axis. As a result the side wall can be deployed and packaged in both directions of the central axis and the radius of the side wall by folding the segments along the connecting creases thereof in the closing and opening patterns.

What is claimed is:  
     
       1. A tube-like deployable structure being foldable as a whole, the structure comprising: 
       a side wall having a tube-like shape defined by a locus of a closed curve moved along an axis, and comprising a plurality of segments foldable in directions of the axis and the closed curve;  
       wherein connecting creases of at least four adjacent segments are connected with one another at one point, the at least four adjacent segments having two patterns of folding, one of which is a closing pattern where the segments are folded to reduce an inner angle between connecting sides of segments adjacent each other in a circumferential direction on the closed curve as accompanied with a folding in the axial direction, another pattern of which is an opening pattern where the segments are folded to enlarge the inner angle between connecting sides of segments adjacent each other on the closed curve, as accompanied with a folding in the axial direction and the side wall being deployed and folded in the axial direction and radially in a direction of a plane by folding the segments according to the closing pattern and opening pattern with the closed curve being in a continuously closed configuration, wherein the diameter of the non-deployed structure is less than the diameter of the deployed structure.  
     
     
       2. A tube-like deployable structure as claimed in claim  1 , wherein the closed curve comprises an approximately circular shape. 
     
     
       3. A tube-like deployable structure as claimed in claim  1 , wherein the opening pattern and the closing pattern are alternating with each other in the direction of the continuously closed curve. 
     
     
       4. A deployable structure as claimed in claim  1 , wherein the closing pattern and the opening pattern are continued in the direction of the central axis, respectively. 
     
     
       5. A tube-like deployable structure as claimed in claim  1 , wherein the axis is a straight line. 
     
     
       6. A tube-like deployable structure as claimed in claim  1 , wherein each segment comprises a quadrangular shape. 
     
     
       7. A tube-like deployable structure as claimed in claim  1 , wherein the side wall comprises modules of a determined number of connected segments, the modules being connected to one another in the axial direction and in a radial direction of the continuously closed curve; 
       each module having four segments folded by the closing pattern, wherein two adjacent segments in the direction of the closed curve have an approximately same length relative to each other in the direction of the closed curve; and  
       when the side wall is folded in the direction of the axis, the respective modules are also folded to have an angle so that segments of the respective modules in the direction of the closed curve are brought into contact with each other, when the tube-like deployable structure is viewed from the direction of the axis when the tube-like deployable structure is folded in its smallest state.  
     
     
       8. A deployable structure as claimed in claim  7 , wherein the module comprises four segments and is folded in a closing pattern manner, and two segments adjacent in the circumferential direction comprise an approximately same length to each other in the circumferential direction. 
     
     
       9. A tube-like deployable structure as claimed in claim  1 , wherein the side wall comprises modules having a determined number of connected segments, the modules are connected to one another in the direction of the axis and in the direction of the closed curve, the module comprises a portion wherein first to third segments are connected to each other in the direction of the closed curve to make two rows in the direction of the axis, the first segments and the second segments are folded by the closing pattern, while the second segments and the third segments are folded by the opening pattern, and when the side wall is folded in the direction of the axis, the first segments and the second segments are folded so that the second segments are approximately overlapped with the first segments. 
     
     
       10. A tube-like deployable structure as claimed in claim  1 , wherein the side wall comprises at least one unit having a ring shape, in which determined number of modules are connected. 
     
     
       11. A tube-like deployable structure as claimed in claim  10 , wherein the deployable structure comprises a shape which is symmetric about the axis when the deployable structure is in a folded state when the tube-like deployable structure is viewed from the direction of the axis and a maximum number of overlapping of the segments is not more than four for one unit. 
     
     
       12. A tube-like deployable structure as claimed in claim  10 , wherein the deployable structure comprises a shape which is symmetric about the axis when the deployable structure is in a folded state when the tube-like deployable structure is viewed from the direction of the axis and a maximum number of overlapping of the segments is more than four for one unit. 
     
     
       13. A tube-like deployable structure as claimed in claim  10 , wherein the deployable structure comprises a shape which is symmetric about the axis of the deployable structure when the deployable structure is in a folded state. 
     
     
       14. A deployable structure as claimed in claim  1  is applied as a dust shield which protect a space system.